JP4994606B2 - Halogen-free insulated wires and wire harnesses - Google Patents

Description

  The present invention relates to a halogen-free insulated wire and a wire harness, and more particularly to a halogen-free insulated wire having a multilayer structure and a wire harness using the same.

  2. Description of the Related Art Conventionally, for example, an insulated wire in which a coating material made of a resin composition is coated on the outer periphery of a conductor is widely used for wiring such as vehicle parts and electrical / electronic equipment parts. Among these types of insulated wires, especially for insulated wires applied to parts that require heat resistance, the type and amount of heat stabilizers and plasticizers to be added, the degree of polymerization, etc. can be adjusted as the coating material. A vinyl chloride resin composition having improved heat resistance by being subjected to crosslinking has been used.

  However, since this type of vinyl chloride resin composition contains a halogen element, it releases harmful halogen-based gases to the atmosphere during combustion such as in the event of a vehicle fire or incineration and disposal of electrical and electronic equipment. There was a problem of causing environmental pollution.

  Therefore, from the viewpoint of reducing the burden on the global environment, in recent years, so-called non-halogen flame retardant, in which a metal hydrate such as magnesium hydroxide is added as a non-halogen flame retardant to an olefin resin such as polyethylene. Alternatives to resin compositions are underway.

  However, olefinic resins are basically flammable, and non-halogen flame retardants are inferior in flame retardancy compared to halogen flame retardants. Therefore, in the non-halogen flame retardant resin composition, it is necessary to add a large amount of metal hydrate in order to ensure sufficient flame retardancy, resulting in wear resistance, tensile elongation, tensile strength, etc. There was a drawback that the mechanical properties of the material significantly deteriorated.

  Therefore, in order to compensate for such drawbacks, for example, in Patent Document 1, a metal hydrate and a crosslinking aid are added to a resin component containing polyethylene or α-olefin copolymer and ethylene copolymer or rubber. A flame retardant resin composition which is added and further contains a specific functional group is disclosed.

Japanese Patent No. 3280105

  However, an insulated wire in which a conventionally known flame-retardant resin composition is coated on the outer circumference of a conductor is still insufficient in electric wire characteristics such as heat resistance, wear resistance, flexibility, etc., and it is necessary to further improve this. there were.

  Therefore, the problem to be solved by the present invention is to provide a halogen-free insulated wire having sufficient flame retardancy and excellent heat resistance, wear resistance and flexibility.

  Moreover, it is providing the wire harness containing this non-halogen-type insulated wire.

In order to solve these problems, the non-halogenous insulated wire according to the present invention has an outer layer coated with an inner layer composed of one or more layers, and an outermost layer is coated on the outer periphery of the inner layer. is is in the range of 10 to 40 [mu] m, the outermost layer, olefin melting point is above 180 ° C. resins and / or _{-Si (X 1) (X 2} ) (X 3) group _{(wherein, X} 1, X is _2, X _3, made from an alkyl or alkoxy group, at least one olefin-based resin having an alkoxy group), made of a resin composition comprising 20 wt% or more, at least one layer of the inner layer, ( A) 50 to 5 parts by weight of an olefin resin having a melting point of 180 ° C. or higher, (B ) 50 to 95 parts by weight of an olefin resin (excluding the olefin resin of the above (A)), and (C) metallic water Japanese 30-2 It consists of a resin composition containing 50 parts by weight.

At this time, 50 to 95 parts by weight of the component (B) include styrene-ethylene-butylene-styrene block copolymer, modified styrene-ethylene-butylene-styrene block copolymer, olefin crystal-ethylenebutylene-olefin crystal. 10.5-60 mass% of 1 type, or 2 or more types of copolymers selected from the block copolymer and the ethylene-vinyl acetate copolymer may be contained. And in the case where the outermost layer is made of a resin composition containing 20% by weight or more of an olefin resin having a melting point of 180 ° C. or higher, the elastic modulus of the olefin resin having an inner layer (A) melting point of 180 ° C. or higher is The melting point in the outermost layer is preferably not more than the elastic modulus of the olefin resin having a temperature of 180 ° C. or higher.

  Further, the outermost layer and / or the inner layer is preferably crosslinked.

  On the other hand, the wire harness which concerns on this invention makes it a summary to comprise the said non-halogen-type insulated wire.

  The non-halogenous insulated wire according to the present invention has a multilayer structure, and the outermost layer is formed of a specific resin composition with a thickness within a specific range, and at least of the inner layers composed of one or more layers. One layer consists of a specific resin composition.

  Therefore, according to the non-halogenous insulated wire, the inner layer contains a specific amount of metal hydrate, and therefore has sufficient flame retardancy.

  Moreover, since it has the specific outermost layer and the inner layer, even when applied to a part exposed to a relatively high temperature, for example, around the engine room of an automobile, the covering material melts, It is not easily deformed by heat and has excellent heat resistance.

  Further, the resin composition forming the outermost layer is not highly filled with metal hydrate. Therefore, compared to a conventional insulated wire coated with a single layer of a flame retardant resin composition containing a large amount of metal hydrate, the mechanical properties such as abrasion resistance are particularly excellent because of the outermost layer.

  Moreover, since it has the said specific outermost layer and inner layer, it is excellent also in a softness | flexibility.

  At this time, when the elastic modulus of the olefin resin having the melting point (A) of 180 ° C. or higher in the inner layer is equal to or lower than the elastic modulus of the olefin resin having a melting point of 180 ° C. or higher, the wear resistance of the outermost layer. The flexibility of the inner layer is further improved.

  Moreover, when the said outermost layer and / or inner layer are bridge | crosslinked, heat resistance improves further.

  Moreover, since the wire harness which concerns on this invention contains the said non-halogen-type insulated wire, it has sufficient flame retardance and is excellent in heat resistance, abrasion resistance, and a softness | flexibility.

  Therefore, the non-halogenous insulated wire and the wire harness can be suitably used particularly for a portion subjected to high temperature load, vibration, etc., and can exhibit high reliability over a long period of time.

  Hereinafter, embodiments of the present invention will be described in detail. In the following, the non-halogenous insulated wire according to this embodiment may be referred to as “main wire”, and the wire harness according to the present embodiment may be referred to as “main wire harness”. ).

1. This electric wire has a multilayer structure in which the outer layer of the conductor is coated with the inner layer, and the outer layer of the inner layer is coated with the outermost layer.

1.1 Conductor Examples of the conductor include a single metal wire, a wire in which a plurality of metal wires are twisted together, a wire in which a plurality of metal wires are twisted and further compressed, and the like. Moreover, the conductor diameter, the material of the conductor, and the like are not particularly limited, and can be appropriately selected depending on the application.

1.2 Outermost layer In this electric wire, the outermost layer has a thickness in the range of 10 to 100 μm. Preferably, it is in the range of 15-60 μm, more preferably in the range of 20-50 μm.

  When the thickness of the outermost layer is thinner than 10 μm, there is a tendency that sufficient wear resistance is hardly obtained, while when it is thicker than 100 μm, there is a tendency that sufficient flame retardancy is hardly obtained. Therefore, the thickness of the outermost layer may be determined in consideration of these.

Here, the outermost layer is composed of an olefin resin having a melting point of 180 ° C. or higher and / or a —Si (X ₁ ) (X ₂ ) (X ₃ ) group (where X ₁ , X ₂ , and X ₃ are alkyl groups. Or an outer resin composition comprising an olefin resin having an alkoxy group and at least one of which is an alkoxy group.

That is, the outer resin composition may include any one of an olefin resin having a melting point of 180 ° C. or higher and an olefin resin having a —Si (X ₁ ) (X ₂ ) (X ₃ ) group, Alternatively, both may be included. In addition, the olefin resin having a melting point of 180 ° C. or more and the olefin resin having a —Si (X ₁ ) (X ₂ ) (X ₃ ) group may each be composed of one kind of resin, or two or more kinds. These resins may be mixed.

  Specific examples of the olefin resin having a melting point of 180 ° C. or higher contained in the outer resin composition include polymethylpentene. The polymethylpentene may be a mixture of a plurality of different physical properties such as elastic modulus.

On the other hand, the olefin resin having a —Si (X ₁ ) (X ₂ ) (X ₃ ) group contained in the outer resin composition is —Si (X ₁ ) (X ₂ ) (X ₃ ) The group may be introduced in any form. Specific examples of X ₁ , X ₂ and X ₃ include a methyl group, an ethyl group, a propyl group, a butyl group, a methoxy group, an ethoxy group, a β-methoxyethoxy group, and a butoxy group.

Specific examples of the olefin resin having a —Si (X ₁ ) (X ₂ ) (X ₃ ) group include, for example, —Si (X ₁ ) (X in the main chain and / or side chain of the olefin resin. ₂ ) A compound in which an (X ₃ ) group-containing compound is grafted using a peroxide or the like, or an olefin and / or an olefin-based resin and a —Si (X ₁ ) (X ₂ ) (X ₃ ) group-containing compound Examples thereof include those obtained by copolymerization.

Specific examples of the -Si (X ₁ ) (X ₂ ) (X ₃ ) group-containing compound include vinyltrimethoxysilane, vinyltriethoxysilane, and γ-methacryloxypropyltrimethoxysilane. . These may be used alone or in combination of two or more.

  Specific examples of the olefin include ethylene, propylene, ethylene-vinyl acetate, and ethylene-acrylate. These may be used alone or in combination of two or more.

  Specific examples of the olefin resin include high density polyethylene (HDPE), medium density polyethylene (MDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), and ultra low density polyethylene ( VLDPE), polypropylene (homo, block, random), polybutylene, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethylene-butyl acrylate Copolymer, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-methylpentene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, ethylene-dodecene copolymer, olefin crystal- Ethylene butylene Such as crystalline olefin block copolymer. These may be used alone or in combination of two or more.

In the outer resin composition, an olefin resin having a melting point of 180 ° C. or higher and / or an olefin resin having a —Si (X ₁ ) (X ₂ ) (X ₃ ) group is contained at least 20% by weight or more. Yes. Preferably, it is 25% by weight or more, and more preferably 30% by weight or more.

When the content of the olefin resin having a melting point of 180 ° C. or higher and / or the olefin resin having a —Si (X ₁ ) (X ₂ ) (X ₃ ) group is less than 20% by weight, for example, a high temperature of 180 ° C. or higher This is because the heat resistance is lowered, for example, the electric wires are thermally fused together and the amount of heat deformation of the covering material is increased.

  Other components in the outer resin composition include, for example, the above-mentioned olefin resin, a block copolymer obtained by copolymerizing styrene and butadiene, a block copolymer obtained by copolymerizing styrene and ethylene-propylene, and hydrogen on these block copolymers. Examples thereof include polymers in which double bonds have been removed by addition, styrene-ethylenebutylene-olefin crystal block copolymers, and the like. These may be used alone or in combination.

  In addition, for example, crosslinking accelerators (such as silanol condensation catalysts such as dibutyltin dilaurate, dibutyltin diacetate, and dibutyltin dioctate), heat stabilizers (such as antioxidants and antioxidants), metal deactivators (such as copper damage prevention) Agents), lubricants (fatty acid, fatty acid amide, metal soap, hydrocarbon (wax), ester, silicon, etc.), light stabilizer, nucleating agent, antistatic agent, colorant, flame retardant Auxiliaries (silicon, nitrogen, zinc borate, phosphorus, etc.), coupling agents (silane, titanate, etc.), softeners (process oil, etc.), zinc compounds (zinc oxide, zinc sulfide, etc.), etc. 1 type, or 2 or more types may be suitably added.

  Further, the resin component contained in the outer resin composition may be modified with an acid. Examples of the acid include unsaturated carboxylic acids and derivatives thereof. Specific examples of the unsaturated carboxylic acid include maleic acid and fumaric acid, and examples of the unsaturated carboxylic acid derivative include maleic anhydride, maleic acid monoester, and maleic acid diester. These may be used alone or in combination of two or more. This type of acid can be introduced by a graft method, a direct (copolymerization) method, or the like.

1.3 Inner layer In this electric wire, the inner layer may consist of only one layer, or two or more layers may be laminated. When the inner layer is composed of two or more layers, the materials, thicknesses, etc. of each layer may be the same or different.

  However, at least one of the inner layers needs to be made of a specific inner resin composition. In addition, the inner layer which consists of this inner side resin composition may be located in any layer.

  Here, the inner resin composition includes (A) an olefin resin having a melting point of 180 ° C. or higher, (B) an olefin resin, and (C) a metal hydrate.

  As the component (A), the same resin as the olefin resin having a melting point of 180 ° C. or higher in the above-described outer resin composition can be used.

  However, (A) the olefin resin having a melting point of 180 ° C. or higher used for the inner resin composition has an elastic modulus equal to or lower than that of the olefin resin having a melting point of 180 ° C. or higher used for the outer resin composition. It is good to choose. This is because such a configuration can further improve the wear resistance of the outermost layer, the flexibility of the inner layer, and the like.

  Moreover, the thing similar to the olefin resin in the outer side resin composition mentioned above can be used for the said (B) component.

  The (C) metal hydrate is used as a flame retardant, and specifically includes magnesium hydroxide, aluminum hydroxide, zirconium hydroxide, hydrated magnesium silicate, hydrated aluminum silicate, basic magnesium carbonate. And compounds having a hydroxyl group or crystal water such as hydrotalcite. These may be used alone or in combination of two or more.

At this time, the particle size of the metal hydrate to be used varies depending on the type, but when the magnesium hydroxide, aluminum hydroxide or the like is used, the average particle size (d ₅₀ ) is 0.1 to 20 μm, preferably 0.8. It is desirable to be in the range of 2 to 10 μm, more preferably 0.3 to 5 μm. If the average particle size is less than 0.1 μm, secondary agglomeration occurs between the particles, and the mechanical properties tend to decrease. If the average particle size exceeds 20 μm, the mechanical properties decrease, This is because there is a tendency to cause rough appearance.

  The particle surface is surface-treated with a surface treating agent such as a coupling agent (silane or titanate such as aminosilane, vinyl silane, epoxy silane, or acrylic silane) or fatty acid (stearic acid or oleic acid). Also good. Moreover, even if such surface treatment is not performed, for example, an integral blend (added simultaneously as a compounding agent at the time of resin mixing) may be performed, and is not particularly limited. The coupling agent may be used alone or in combination of two or more.

  In the inner resin composition, the blending ratio of each component is 50 to 5 parts by weight of component (A), preferably 40 to 10 parts by weight, and 50 to 95 parts by weight of component (B), preferably 60 to 90 parts by weight. The total amount of the components (A) and (B) is 100 parts by weight, and the component (C) is in the range of 30 to 250 parts by weight, preferably 50 to 200 parts by weight, more preferably 60 to 180 parts by weight. And good. This is because the electric wire is excellent in various physical properties such as flame retardancy, heat resistance, wear resistance, and flexibility as long as it is within this blending ratio range.

  In addition to the components (A) to (C), various additives similar to those of the outer resin composition may be added as appropriate to the inner resin composition.

  When the inner layer is composed of two or more layers, a non-halogen flame retardant resin composition having physical properties within a range that does not impair the required physical properties of the electric wire may be used for the inner layer other than the inner layer made of the inner resin composition. it can.

  The basic configuration of the electric wire has been described above. The electric wire is not particularly limited, such as the conductor diameter and the thickness of the entire covering material. Usually, the outer diameter of the electric wire is φ5 mm or less, preferably φ4 mm or less, and a covering material that combines the inner layer and the outermost layer. The thickness is 0.8 mm or less, preferably 0.4 mm or less, and can be suitably used as a thin and thin wire.

  In addition, the outermost layer and the inner layer may be crosslinked with radiation, a peroxide, a silane-based crosslinking agent, or the like from the viewpoint of further improving heat resistance.

  In this electric wire, the outermost layer may be directly coated on the outer periphery of the inner layer, or another intermediate member such as a shield conductor such as a braid or metal foil is interposed between the inner layer and the outermost layer. The outer periphery of this inclusion may be covered.

2. Manufacturing method of this electric wire As a manufacturing method of this electric wire, the method generally known can be used and it is not specifically limited. For example, first, each component is optionally blended with other components and additives as necessary, and these are dry blended with a normal tumbler or the like, or a Banbury mixer, a pressure kneader, a kneading extruder, The outer resin composition and the inner resin composition are prepared by melt-kneading and uniformly dispersing in a normal kneader such as a shaft extruder or roll.

  Next, for example, the outer periphery of the conductor is coated with the inner resin composition with an arbitrary thickness using an extruder, and the outer periphery of the inner layer is coated with the outer resin composition so as to have a specified thickness. This electric wire can be obtained. Moreover, if the obtained electric wire is optionally irradiated with radiation or the like, a crosslink can be formed in the coating material.

3. This wire harness protects the wire harness from a single wire bundle in which only this wire is bundled together, or a mixed wire bundle in which this wire and other insulated wires are bundled together. It is covered with a material.

  The number of wires included in the single wire bundle and the mixed wire bundle can be arbitrarily determined and is not particularly limited.

  In addition, when using a mixed wire bundle, the structure of the other insulated wires included is not particularly limited, and even if one layer of the coating material is coated, two or more layers are coated. May be. Moreover, the kind of coating material of another insulated wire is not specifically limited.

  Further, the wire harness protective material has a role of covering the outer periphery of the wire bundle and protecting the inner wire bundle from the external environment, etc., and an adhesive is applied to at least one surface of the tape-shaped substrate. Examples include those coated and those having a substrate formed in a tube shape, a sheet shape, or the like. These can be appropriately selected and used according to the application.

  Specific examples of the substrate constituting the wire harness protective material include, for example, various non-halogen flame retardant resin compositions, vinyl chloride resin compositions, or halogen resin compositions other than the vinyl chloride resin compositions. Can be mentioned.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

(Test material and manufacturer)
The test materials used in this example are shown together with the manufacturer, product name, physical property values, and the like.

(Outermost layer)
Polymethylpentene <1> (TPX <1>) [Mitsui Chemicals, trade name “TPX MX002”, flexural modulus measured according to ASTM D790 = 640 MPa]
Polymethylpentene <2> (TPX <2>) [Mitsui Chemicals, trade name “TPX DX820”, flexural modulus measured according to ASTM D790 = 1570 MPa]
_{· -Si (X 1) (X} 2) (X 3) polypropylene having a group _{(-Si (X 1) (X} 2) (X 3) PP having a group) [Mitsubishi Chemical Co., Ltd., trade name " Linklon XPM800HM "]
_{· -Si (X 1) (X} 2) (X 3) high density polyethylene having a group _{(-Si (X 1) (X} 2) (X 3) HDPE having a group) [Mitsubishi Chemical Co., Ltd., trade Name “LINKRON XHE650N”]
-Polypropylene (PP) [Nippon Polypro Co., Ltd., trade name "Novatec EC9"]
・ Polyethylene <1> (PE <1>) [Mitsui Chemicals, trade name “Hi-Zex 5305E”
・ Crosslinking accelerator <1> [Made by Mitsubishi Chemical Corporation, trade name “PZ010S”
・ Crosslinking accelerator <2> [Mitsubishi Chemical Corporation, trade name "LZ015H"
Anti-aging agent <1> [trade name “Irganox 1010” manufactured by Ciba Specialty Chemicals Co., Ltd.]

(Inner layer)
Component (A): Polymethylpentene <1> (TPX <1>) [Mitsui Chemicals, trade name “TPX MX002”, flexural modulus measured according to ASTM D790 = 640 MPa]
Polymethylpentene <2> (TPX <2>) [Mitsui Chemicals, trade name “TPX DX820”, flexural modulus measured according to ASTM D790 = 1570 MPa]
Component (B): Polypropylene (PP) [Nippon Polypro Co., Ltd., trade name “NOVATEC EC9”]
・ Polyethylene <1> (PE <1>) [Mitsui Chemicals, trade name “Hi-Zex 5305E”
-Polyethylene <2> (PE <2>) [Nippon Polyethylene Co., Ltd., trade name "Kernel KF283"
・ Styrene-ethylene-butylene-styrene block copolymer (SEBS) [Asahi Kasei Chemicals Corporation, trade name “Tuftec H1041”]
-Modified styrene-ethylene-butylene-styrene block copolymer (modified SEBS) [Asahi Kasei Chemicals Co., Ltd., trade name "Tuftec M1913"]
-Olefin crystal-ethylene butylene-olefin crystal block copolymer (CEBC) [manufactured by JSR Corporation, trade name "DYNARON 6200P"]
・ Ethylene-vinyl acetate copolymer (EVA) [Mitsui / Dupont Polychemical Co., Ltd., trade name “EVAFLEX EV360”]

Component (C) Magnesium hydroxide [manufactured by Martinsberg, trade name “Magnifine H10”, average particle size of about 1.0 μm]

Other Ingredients / Anti-aging Agent <1> [trade name “Irganox 1010” manufactured by Ciba Specialty Chemicals Co., Ltd.]
Anti-aging agent <2> [manufactured by Sipro Kasei Co., Ltd., trade name “Seenox 412S”]
Anti-aging agent <3> [Product name “ANTAGE MB” manufactured by Kawaguchi Chemical Industry Co., Ltd.]
Copper damage inhibitor [Asahi Denka Kogyo Co., Ltd., trade name "CDA-1"]
・ Zinc oxide [Hakusuitec Co., Ltd., Zinc Hana]
・ Zinc sulfide [product name “Sachtolith HD” manufactured by Sachtleben]

(Production of outer and inner resin compositions and insulated wires)
First, using a twin-screw extruder, the components shown in the table to be described later are kneaded to produce an outer resin composition and an inner resin composition compound (pellet) used for insulated wires according to Examples and Comparative Examples. did.

Then, after drying each obtained pellet, an inner resin composition was coated on the outer periphery of a conductor of size 0.50 fmm ² (19 / 0.19) by an extruder to form an inner layer, Further, the outer periphery of the inner layer was coated with an outer resin composition to form an outermost layer. At this time, the total coating thickness of the inner layer and the outermost layer was 0.28 mm. Further, the thickness of the outermost layer is as described in the table described later. The outer diameter of each electric wire is φ1.53 mm.

Next, in the outer resin composition, the insulated wire containing the olefin resin having a -Si (X ₁ ) (X ₂ ) (X ₃ ) group is further immersed in warm water at 85 ° C. for 24 hours. , Dried. This produced the halogen-free insulated wire according to the present example and the halogen-free insulated wire according to the comparative example.

(Test method)
About the non-halogen-based insulated wire according to the present example and the non-halogen-based insulated wire according to the comparative example manufactured as described above, flame retardancy test, high-temperature self-diameter winding test, heat deformation test, wear resistance test, flexibility test Went. Each test method and evaluation method will be described below.

(Flame retardancy test)
This was performed in accordance with JASO D611. That is, the non-halogen-based insulated wire according to the present example and the non-halogen-based insulated wire according to the comparative example were cut into a length of 300 mm to obtain test pieces. Next, each test piece is put in an iron test box and supported horizontally, and the tip of the reducing flame is applied using a Bunsen burner with a diameter of 10 mm from the lower side of the center of the test piece until it burns within 30 seconds, and the flame is gently The afterflame time after removal was measured. Those having a residual flame time of 15 seconds or less were accepted and those exceeding 15 seconds were rejected.

(High temperature self-diameter winding test)
A non-halogenous insulated wire according to this example and a non-halogenated insulated wire according to a comparative example were wrapped 6 times around an object having a diameter equal to the outer diameter of each wire, heated in a constant temperature bath at 180 ° C. for 30 minutes, Until cooled. As a result, the case where cracks and melting did not occur in the coating material was accepted, and the case where cracks and melting occurred was rejected.

(Heating deformation test)
This was performed in accordance with JIS C 3005. That is, the coating material thickness before heating was measured for the non-halogen-based insulated wire according to this example and the non-halogen-based insulated wire according to the comparative example. Next, each of these insulated wires was put in a testing machine preheated to 180 ° C. and heated for 30 minutes. Next, each insulated wire was placed between the parallel plates of the measuring device, a load of 150 kgf was applied thereto, and the temperature was further maintained at the same temperature for 30 minutes. Next, the thickness of the coating material after heating was measured for each insulated wire as it was. Next, the reduction rate [%] was calculated from the following formula.
Decrease rate [%] = (Thickness of coating material before heating [mm] −Thickness of coating material after heating [mm]) / Thickness of coating material before heating [mm] × 100
As a result, a reduction rate of 40% or less was accepted, and a percentage exceeding 40% was rejected.

(Abrasion resistance test)
The non-halogenous insulated wire according to this example and the non-halogenated insulated wire according to the comparative example were respectively inserted into a corrugated tube, and vibrated under conditions of frequency 30 Hz, acceleration 44.0 m / s ² , temperature 100 ° C., and 240 hours. Was added. At this time, the case where the coating material was worn and the conductor was not exposed was regarded as acceptable, and the case where the conductor was exposed was regarded as unacceptable.

(Flexibility test)
The non-halogen-based insulated wire according to this example and the non-halogen-based insulated wire according to the comparative example were judged by hand feeling when bent by hand. That is, those with good tactile sensations were accepted and those with poor tactile sensations were rejected.

  Tables 1 and 2 below show the component composition and evaluation results of the outermost layer and the inner layer in the non-halogen-based insulated wire according to this example and the non-halogen-based insulated wire according to the comparative example.

  According to Table 2 above, the halogen-free electric wire according to the comparative example has difficulty in any of the evaluation items of flame retardancy, high-temperature self-diameter winding test, heating deformation test, wear resistance test, and flexibility test. I understand that there is.

  That is, more specifically, in Comparative Example 1, since the olefin-based resin having a melting point of 180 ° C. or higher is less than the specified amount in the resin composition of the outermost layer, it is melted or the amount of heat deformation is increased. Inferior in heat resistance.

  Moreover, since the comparative example 2 does not contain the olefin resin (A) whose melting point is 180 ° C. or higher in the resin composition of the inner layer, the amount of heat deformation increases and the heat resistance is poor.

  Moreover, since the ratio of the (C) metal hydrate in the resin composition of an inner layer is less than a regulation range, the comparative example 3 is inferior in a flame retardance.

  Further, Comparative Example 4 is inferior in flexibility because the ratio of (C) metal hydrate in the inner layer resin composition is greater than the specified range.

  Moreover, since the thickness of the outermost layer is thinner than a regulation range, the comparative example 5 is inferior to abrasion resistance. In addition, when there is no outermost layer, it is clear that it is inferior to this comparative example 5 or more in abrasion resistance.

  Moreover, since the thickness of the outermost layer is thicker than a regulation range, the comparative example 6 is inferior in a flame retardance.

In Comparative Example 7, the resin composition of the outermost layer contained less —olefin (Si (X ₁ ) (X ₂ ) (X ₃ )) than the prescribed amount. It is inferior in heat resistance, such as increasing.

  On the other hand, according to Table 1 above, it was confirmed that the halogen-free electric wire according to the present example was excellent in all of flame retardancy, heat resistance, wear resistance, and flexibility.

Claims (5)

A non-halogen-based insulated electric wire in which an inner layer composed of one or more layers is coated on the outer periphery of the conductor, and an outermost layer is coated on the outer periphery of the inner layer,
The thickness of the outermost layer is in the range of 10 to 40 μm,
The outermost layer is composed of an olefin resin having a melting point of 180 ° C. or higher and / or a —Si (X ₁ ) (X ₂ ) (X ₃ ) group (where X ₁ , X ₂ , and X ₃ are alkyl groups or alkoxy groups. made, the olefin resin having at least one is an alkoxy group), made of a resin composition comprising 20 wt% or more,
At least one of the inner layers is
(A) 50 to 5 parts by weight of an olefin resin having a melting point of 180 ° C. or more, (B ) 50 to 95 parts by weight of an olefin resin (excluding the olefin resin of (A) above), and (C) a metal A non-halogenous insulated wire comprising a resin composition containing 30 to 250 parts by weight of a hydrate. The component (B) contains 50 to 95 parts by weight of styrene-ethylene-butylene-styrene block copolymer, modified styrene-ethylene-butylene-styrene block copolymer, olefin crystal-ethylenebutylene-olefin crystal block copolymer. 2. The halogen-free insulated wire according to claim 1, comprising 10.5 to 60% by mass of the polymer and one or more copolymers selected from ethylene-vinyl acetate copolymers. .
The outermost layer is made of a resin composition containing 20 wt% or more of an olefin resin having a melting point of 180 ° C. or higher, and (A) the elastic modulus of the olefin resin having a melting point of 180 ° C. or higher in the inner layer is 3. The non-halogenous insulated wire according to claim 1, wherein the outermost layer has a melting point of 180 ° C. or more and an elastic modulus of the olefin resin or less. The non-halogenous insulated wire according to any one of claims 1 to 3 , wherein the outermost layer and / or the inner layer is cross-linked. A wire harness comprising the non-halogenous insulated wire according to any one of claims 1 to 4 .